Chromatographic size separation of single-wall carbon nanotubes

Received: 18 May 1998/Accepted: 22 May 1998     

Force measurements of optical tweezers in electro-optical cages

Received: 19 May 1998/Accepted: 28 May 1998     

Monocrystalline Si waffles for thin solar cells fabricated by the novel perforated-silicon process

2 for this waffle-shaped film when it is attached to glass substrates. Received: 15 May 1998/Accepted: 28 May 1998     

Diode-laser-seeded optical parametric oscillator for airborne water vapor DIAL application in the upper troposphere and lower stratosphere

Received: 4 May 1998/Revised version: 17 July 1998     

Influence of a magnetic field on deposition of diamond-like carbon films

Received: 17 February 1998/Accepted: 25 May 1998     

Application of laser-guided discharge to processing

Received: 5 May 1998/Accepted: 14 August 1998     

Cathodoluminescence from nanocrystalline silicon films and porous silicon

Received: 4 May 1998 / Accepted: 30 October 1998     

Intracavity frequency mixing in pulsed optical parametric oscillators for the efficient generation of continuously tunable ultraviolet radiation

Received: 4 May 1998/Revised version: 8 July 1998     

Electrical properties of Au–polystyrene–Au submicron structures

Received: 25 January 1998/Accepted: 28 May 1998     

Scattering and extinction of evanescent waves by small particles

Received: 14 May 1998/Revised version: 31 July 1998     

Inverse metal-stripe polarizers

Received: 18 May 1998/Revised version: 17 August 1998     

Second-harmonic imaging of ferroelectric domains in LiNbO3 with micron resolution in lateral and axial directions

Received: 22 May 1998/Revised version: 10 July 1998     

Cooperative diffusion in weakly charged polyelectrolyte gels

A general expression for the cooperative diffusion constant of weakly charged gels is derived as a function of the thermodynamic parameters such as polyelectrolyte concentration, salt concentration, ionic strength, and the degree of crosslinking. In the low concentration range it decreases with the monomer concentration. Received: 30 January 1998 / Revised: 4 May 1998 / Accepted: 6 May 1998     

Modeling for laser-induced surface thermal lens in semiconductors

Received: 14 December 1997/Revised version: 19 May 1998     

Expansions for the eigenvalues of three-term recurrence relations. Two applications in molecular physics

Approximate expressions for the eigenvalue of a three-term recurrence relation with a general form describing various physical problems are proposed. Their range of availability is examined by comparison with exact values for two different problems: the bound and continuum states of monoelectronic diatomic ions and the Schr?dinger equation describing molecular alignment in intense laser fields. For each case, very good predictions have been obtained, which may be useful as initial values in iterative procedures for deriving exact solutions. Received: 30 January 1998 / Received in final form: 10 April 1998 / Accepted: 25 May 1998     

Photo induced collisions with laser cooled He* atoms

This paper presents an experimental investigation of cold collisions between metastable helium atoms in an optical trap at 1 mK. Penning (PI) and associative (AI) ionization reactions are distinguished using a mass spectrometer and studied under influence of near resonant laser light. Dramatic enhancement, by more than a factor 15, of the ion rate is observed when the laser is tuned close to resonance. Experimental findings are well-described, on an absolute scale, by model predictions. Received: 9 February 1998 / Revised: 4 May 1998 / Accepted: 14 May 1998     

On the Fermi surface of some organic superconductors with sizeable critical temperatures

Recent studies of the Fermi surface of quasi-two-dimensional organic conductors comfort the idea that the presence of a van Hove anomaly near the Fermi level is a favourable factor for superconductivity. Received: 28 April 1998 / Revised and accepted: 13 May 1998     

Well-defined Co clusters embedded in an Ag matrix: A model system for the giant magnetoresistance in granular films

Well-defined granular Co/Ag films have been prepared by the co-deposition of in-beam prepared Co clusters and Ag atoms. In this way we were able to study the giant magnetoresistance (GMR) as a function of mean Co cluster size for a fixed Co cluster volume fraction v_cl as well as a function of v_cl for a fixed . Mean Co cluster size has been varied between and 6.9 nm, Co cluster volume fraction between 5 and 43%. The GMR was measured in-situ at T=4.2 K in magnetic fields 1.2 T. The analysis of the GMR data obtained from these studies clearly shows that spin-dependent scattering at the Co-cluster/Ag-matrix interface is the only relevant scattering mechanism causing the GMR in our well-defined samples. Received: 21 April 1998 / Received in final form: 17 May 1998 / Accepted: 18 May 1998     

Measurement of the Barkas effect in hydrogen

The stopping power of gaseous hydrogen for positive and negative muons at energies ranging from 3 to 100 keV has been measured by time-of-flight. A pronounced Barkas effect was observed: the energy loss in hydrogen for negative muons was found to be significantly smaller than that for positive muons. Received: 23 April 1998 / Accepted: 7 May 1998